\documentclass[E:/GsjzTle/main/main.tex]{subfiles}

\begin{document}

\(A_{i,j}=lcm(i,j)\)，\(O(NM)\)

\begin{lstlisting}
for(int i = 1 ; i <= n ; i ++) for(int j = 1 ; j <= m ; j ++)
if(!a[i][j])
{
	for(int k = 1 ; i * k <= n && j * k <= m ; k ++) 
	a[i * k][j * k] = i * k * j;
}
\end{lstlisting}

\end{document}
